1. Field of the Invention
This invention relates to a strap pressing device for a strap packing apparatus, particularly to one capable to prevent a strap from being scarred or hurt.
2. Description of the Prior Art
A conventional strap packing apparatus 10 shown in FIG. 1 includes a base 11, a cutting device 12 provided beside the base 11, a strap roll supporter 13 and a strap pressing device 14. A lever 15 and a grip 16 are pivotally connected to the base 11 for performing strapping, strap pressing, tightening and cutting. The pressing device 14 is provided with a body 141, a pressing block 142 is pivotally connected to the body 141, and a toque spring 143 located between the body and the pressing block 143 for elastically pressing the pressing block 142 to press tightly overlapped ends of a strap on the base 11. When the lever 15 is pressed down, the cutting device 12 cuts the strap, and at the same time the body 141 of the strap pressing device 14 rotates forward bias, forcing the pressing block 142 also moving forward bias to release the strap pressed so far, finishing retreating of the strap.
However, when the conventional strap pressing device 14 retreats the strap, the pressing block 142 moves together with the body 14 bias to release the strap, but at the beginning of moving bias the pressing block 142 is still moved bias by the torque spring 143, with the sharp front edge and a partial rough bottom surface of the pressing block 142 producing sliding frictionally against the surface of the strap, which is then easily scarred to get cut lines on its surface, resulting in the strap's appearance and worsened in strength resisting tension. And if worse, the strap may be broken off. Moreover, the frictional slide may increase pressing resistance against the lever 15, and strap retreating operation needs more force.